QUADRUMANA. Di 



LAGOTHRix(a), Geoff. — Gastrimargus, Spix. 

 Head round, like the Ateles ; a thumb developed like the Alouattes ; 

 tail partly naked, like tlie one and the other. Such are the L. Humbol- 

 dii, Geoff. ; the Caparo, Humb. ; Gast. olivaceiis, Spix, pi. 28 (the Cap- 

 paro); and the Grison, (or Lax/, canus, Geoff.); or Gastr. infumatus, Spix, 

 29. (The Silver-haired Monkey). Monkeys from the interior of South 

 America, said to be remarkable gluttons. 



The other Sapajous (Cebus, Geoff.) have a round head, distinct thumbs, 

 and the tail hairy, though prehensile. The species are more numerous 

 than those of the Alouatte, and are characterized with nearly as much 

 difficulty. 



Some of them have the hairs on the forehead of a uniform length, such 

 as the — 



Sim. appella, L. (The Sajou) ; and the S. capucina, L. ; Buff. 

 XV. 4, 5, and 8, 9. (The Capuchin). Both of them of different 

 browns ; in the first, the circumference of the face is blackish ; in 

 the second it is whitish ; but the shade of colour in all the rest of 

 their bodies varies between a brownish black and a fawn-colour, 

 sometimes even a white. The shoulders and breast are however 

 generally lighter, and the calotte and hands darker*. 



Others, again, have the hairs of the forehead so disposed as to form a 

 kind of aigrette, such as the 



Sim. fatuellus, Gm. ; Buff. Supp. VII. 29. (The Horned Sajou). 

 This animal has a tuft of black hairs on each side of the forehead f. 



The disposition of these monkeys is mild and gentle, their motions 

 quick and light, and they are easily tamed. Their name of Weeping 

 Monkeys is derived from their soft plaintive voice. 



* The Sajous and the Sais vary so much from a brown to a yellow, that, were there 

 not intermediate varieties, we should be tempted to make many species of them. 

 Such is the case with the Sim. trepida, syrichta, htguhris, flavia, L. and Schreb., as 

 well as some of those distinguished by M. Geoffroy, Ann. du Mus. XIX. 1 1 1 and 112. 

 Spix has recently, and in our opinion improperly, multiplied them still more. 



We would refer to the Sajou {Sim. appella, Lin.) the Cebus rohustus, Pr. Max., 

 which appears to us to be an old one of that species. The Ceb. macroccphalus, Spix, 

 pi. 1, does not seem to differ fi'om it, so far as regards the species. We refer to the 

 Sai {S. capucina, Lin.) the Sai a gorge blanche, Buff. {S. hypolencos) ; the Cebus libi- 

 dinosus, Spix, 2; the Ceb. xanthosternus, Pr. Max., or the Ceb. .rantkocephalus, Spix, 3; 

 the Ceb. cucullalus, id. 6. 



We should be more inclined to consider as distinct species, the Sajoti a pieds dores, 

 Fred. Cuv., the Sajou brun, id. or Ceb. unicolor, Spix, pi. 4; the Sim. flavia, Schreber, 

 31, B, from which the Ceb. gracilis, Spix, pi. 5, seems to differ only in the stuffing 

 — but that we require numerous observations, made upon the spot which these ani- 

 mals inhabit, before we can hope to establish their species in any other than an arbi- 

 trary manner. 



t Here should come the Cebus cirrhifer, Geoff, and the Ceb. of the same name, 

 of Pr. Max., btit which is different. Cib. cristalus, Fred. Cuv. 



^^{a) The existence of this animal was not known until Humboldt discovered it in 

 Soutli America: — He describes it under the name of Simla Lagothrica. A remark- 

 ably fine specimen was presented lately to the Surrey Zoological Gardens, which was 

 brought from Para, on the River Amazon, in Soutli America. Its habitation is now 

 considered to be the northern portion of South America, between tlic Equator and 

 five degrees of nortli latitude. — Eng. Ed. 



